Rudman Regulator

Rudman Regulators

Rudman Regulators come in lots of versions. All of them offer two basic functions. They sit on top of a battery and clamp its voltage to some maximum, keeping it from being overcharged. This is accomplished by shunting power through a resistor on the regulator. They also optionally send a signal back to a Manzanita Micro battery charger (or other charger) telling the charger to cut back its current because one or more batteries can't accept this level of charging current.

All versions before the MK2-D and the MK3 are no longer available.

The MK-1 versions were relatively simple.

The MK-2 versions are much more feature-rich than the MK-1 versions. They allow the user to set the clamping voltage and the voltage considered "too low." If the "too low" voltage is ever encountered, a red LED lights up and stays lit until the battery is fully charged, as evidenced by the voltage clamping circuit engaging. The voltage clamping circuit lights a green LED when it is active. Furthermore, the MK-2 regs can accept a signal from the charger indicating that the clamping voltage should be raised 10% for an equalization charge. When this is turned on, typically by a DIP switch on the charger, the reg turns on a yellow LED. Lastly, the MK-2 series of regulators have a header for an external temperature sensor and an external load, which is turned on when the clamping circuit is engaged.

The MK-3 versions use an embedded microprocessor to do most of the things that the MK-2 series did, except for the external load. A user can connect a computer (or other device) to the string of regulators and collect data from them, vastly simplifying the task of monitoring a battery pack.

The MK-3 regulators respond to a set of commands, which can be entered directly from a computer running a terminal emulator program. Windows XP, for example, comes with "Hyperterminal" which is an example of such a program. If you already know all about terminal emulators, consider this as an example. If you don't know what one is, find a computer running XP and go to Start->All Programs->Accessories->Communications->Hyperterminal. Choose a COM port that you have a "null modem" plugged into. Set the baud rate to 9600. Set the format to 8-N-1. Connect the null modem cable to the adapter that is connected to the regulator string.

All commands follow a two-digit number with no space between them. The two-digit number identifies the individual regulator in the string. Using the number 99 addresses all the regulators simultaneously.

The commands are as follows:

voltage - Displays the current voltage of the battery that the regulators sits on.

Example: 01voltage returns 01V 13.83V

status - Displays the current state of the regulator, including which features are turned on or off and what is currently happening. The result is a two-digit hexadecimal number. Each bit means something.

The definition of the bits is as follows:

Regulator Disabled - 0x80 Shunting Current - 0x40 Battery voltage is too low - 0x20 Battery voltage is too high - 0x10 Battery voltage has been low - 0x08 Regulator is too hot to function - 0x04 Battery temp monitoring enabled - 0x02 Statistical collection enabled - 0x01